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feng_liyong

No overwater equipage In developing a DCB response to moving line of convective weather, one option is to route aircraft through a departure area still open via an overwater reroute that will avoid some of the ground delays (and possibly surface congestion). However, the aggregate ATM System response will be flawed if it is predicated on the effect of rerouting aircraft that lack overwater equipment and are unable to accept the route.
最近在看一些民航ICAO资料，请帮我个忙翻译一下可以吗？这一段内容我实在头疼。

feng_liyong

Multiple aircraft (even if operated by the same airspace user) submit a range of preferences. As illustrated in Figure A11, if airport operation plans landing west and south, aircraft parking east express a preference to land west but aircraft parking west prefer to land south. [Thus aircraft landing west end up on the east side of the airport and aircraft landing south end up on the west side.]

feng liyong

With successful strategic conflict management, the frequency of separation provision actions should be minimized. Separation provision uses an updated trajectory to evaluate for conflicts with hazards. This updated trajectory must reflect the known aircraft state, must reflect clearances to the flight, and may be updated with higher frequency than the shared trajectory as greater accuracy is required for separation
provision than other concept components.

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Flights that are not capable of post-departure negotiation may be provided a re-route during pre-departure planning to minimize the workload and impact during periods with uncertain capacity limitations. As an example, consider Figure B-1. During planning, the specifics of the weather are not known, and airborne re-routing around a future convective weather system may be workload-intensive to ATC. However, flights may wish to plan through the area hoping that the weather will not materialize, or that they may be able to operate through the area due to sparse coverage. Flights that cannot take advantage of post-departure negotiation and the associated execution of the re-route obtain a pre-departure re-route. Flights that are
capable may file through the area with expected convective activity. In-flight these may obtain a re-route in accordance with the more accurate near-real-time weather information.
拜托，再次求助！

feng_liyong

feng_liyong

Prior to take-off, a flight has loaded the clearance into their FMS consistent with the agreed trajectory.
Subsequent to surface movement and prior to take-off, the flight is provided a take-off clearance consistent with the agreed trajectory. The aircraft departs and the trajectory is updated with the actual take-off time for accuracy and shared. New estimated times are more accurate. Aircraft equipped with the capability downlink
an aircraft-derived trajectory to improve the accuracy of the updated trajectory that is shared on the ground.
Flights subject to a time constraint on climb, for example to merge into an overhead flow, depart to meet such a time constraint with minor trajectory modifications in climb.

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subsequent to take-off, a flight with a time constraint to merge into an overhead stream or meter on departure will be provided a take-off time to do so. Adjustments in the time will be required to compensate for the uncertainty. With higher trajectory accuracy at the time constraint, smaller maneuvers are required on climb to compensate for any uncertainty. When uncertainty is lower on the own- ship and surrounding flights, buffers can also be reduced, allowing a greater level of throughput.

overhead stream or meter on departure不知该如何翻译，meter on departure不明白指的是什么？

METERING- A method of time-regulating arrival traffic flow into a terminal area so as not to exceed a predetermined terminal acceptance rate.

METERING FIX- A fix along an established route from over which aircraft will be metered prior to entering terminal airspace. Normally, this fix should be established at a distance from the airport which will facilitate a profile descent 10,000 feet above airport elevation (AAE) or above.

feng_liyong

Constraint
A limitation to free manoeuvring of an aircraft. Limitations are geospatial and temporal in nature and can originate from any GATMOC Component, including AUO (see ICAO Doc.9965, Section 4.4.5 describing operator constraints) as well as from meteorological conditions or local regulations. A constraint can be a trajectory constraint or a generic constraint.
Trajectory constraint
A trajectory constraint limits the freedom of a trajectory by fixing one of its 4D points or segments in one or more dimensions (vertical, lateral, time), with corresponding bounds (“between boundary values”) or direction (“before”, “after”, “above”, etc.) An example is an altitude constraint to avoid restricted airspace.
Generic constraint
A generic constraint consists of known information that limits the solution space for defining a trajectory. Examples include aeronautical information like predefined airspace structures, availability of military airspace for civil use, availability of conditional routes, night curfews, etc. A generic constraint, often caused by restrictions or regulation, may result in a trajectory constraint. Closely associated with constraints are operator preferences which are described in Doc. 9965 in two forms:
Operator preferences
This item includes preferences on operator procedures and other operator specific information impacting manoeuvers and clearances. Unlike operator constraints, the operator would accept these but would prefer not to. Examples include procedures that would adversely affect flight efficiency or a runway preference. This input may or may not be complied with based upon the impact to ATM system performance.

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3.3.1.1 OPEN VERSUS CLOSED CLEARANCES
A closed clearance is an ATC clearance issued to authorise an aircraft to follow a 4D Trajectory. The trajectory is thus deterministic and can be anticipated. These include end-to-end route clearances, “climb via” procedures in the altitude dimension, as well as those ATC clearances resulting in a closed trajectory revision.
For example, a direct from one point to a downstream point allows a continuous trajectory to be constructed, and is therefore a closed clearance.
Clearances that are not closed are said to be open.
An open clearance authorizes or instructs an aircraft to deviate from a 4DT without additional authorization or instruction allowing a new 4DT to be defined. Open clearances include (but are not limited to) heading without a turn-back, track, route or altitude related instructions that need to be closed by a subsequent ATC instruction to allow the flight to complete. Note that information about future clearances (e.g., EXPECT …) cannot be considered a way to close a clearance. Additionally, when a flight is no longer following the aircraft intent, an aircraft-derived trajectory may no longer be available.
While closed clearances are preferred for trajectory-based operations, it is recognized that open clearances may still be required under some circumstances. The following examples illustrate this point:
• A heading instruction may be unsafe to close until an external event happens (e.g. heading needsto be maintained until another aircraft vacates a certain level)
• A pilot cleared to deviate due to weather will probably not be issued a “resume route” clearance until he reports clear of weather
• An aircraft flying a holding pattern can be given an expected time to leave the hold, but will usually not actually be cleared to do so in advance
In these cases, the coordination of a trajectory intention should be achieved as soon as practicable. Even when a flight is operating for some period open-loop, an Agreed Trajectory may be negotiated downstream with tolerances on time to allow the flight to resume operating on the Agreed Trajectory downstream of the open clearance. This Agreed Trajectory allows planning to continue with knowledge of the open clearance effect.

需要帮助，以下内容中heading without a turn-back ,track 不知如何翻译，下两段段多如何理解？谢谢！
Open clearances include (but are not limited to) heading without a turn-back, track, route or altitude related instructions that need to be closed by a subsequent ATC instruction to allow the flight to complete. Note that information about future clearances (e.g., EXPECT …) cannot be considered a way to close a clearance. Additionally, when a flight is no longer following the aircraft intent, an aircraft-derived trajectory may no longer be available.

• A heading instruction may be unsafe to close until an external event happens (e.g. heading needsto be maintained until another aircraft vacates a certain level)
• A pilot cleared to deviate due to weather will probably not be issued a “resume route” clearance until he reports clear of weather
• An aircraft flying a holding pattern can be given an expected time to leave the hold, but will usually not actually be cleared to do so in advance

With successful strategic conflict management, the frequency of separation provision actions should be minimized. Separation provision uses an updated trajectory to evaluate for conflicts with hazards. This updated trajectory must reflect the known aircraft state, must reflect clearances to the flight, and may be updated with higher frequency than the shared trajectory as greater accuracy is required for separation
provision than other concept components.
若有成功的战略冲突规避管理系统，就能有效的避免“防止突破安全间隔而进行的应急规避行为”。“该行为”采用升级版的预测飞行轨迹功能，能有效评估潜在飞行冲突风险。预测飞行轨迹的功能 应能自行把航空器的当时状态，及管制员给与航空器的指令所造成的潜在影响（该指令可能造成航空器冲突，而该功能能把该指令因素也考虑进去）作为相关因素纳入“规避行为”中，这样就能更真实的做出碰撞风险判断 - 例如管制员让航空器下降至某高度层，航空器虽然还没开始下降，但下方确实有其它航空器，系统预先对管制员的指令进行计算，认为管制员的指令可能让飞机发生冲突，就能提供有效告警，然而在旧的计算抛面中，是无法识别管制员的错误危险指令的。 该功能需要更频繁的升级，而且是比其他的共享通用轨迹更频繁的升级，才能提供更准确的飞行轨迹，以进行更精准的突破安全间隔预测告警，